BRD9 promotes the progression of gallbladder cancer via CST1 upregulation and interaction with FOXP1 through the PI3K/AKT pathway and represents a therapeutic target.

Gallbladder cancer (GBC) is highly aggressive and has poor prognosis, with most patients only diagnosed at an advanced stage. Furthermore, treatment options are limited, and their effect is unsatisfactory. Bromodomain-containing protein (BRD) is an epigenetic regulator that plays a carcinogenic role in several tumors, including squamous cell lung cancer, acute myeloid leukemia, synovial sarcoma, and malignant rhabdomyosarcoma. However, the expression, biological function, and molecular mechanisms of action of BRD9 in GBC are still unknown. Kaplan-Meier analysis, qRT-PCR, and analysis of clinical features were used to assess the clinical significance of BRD9 in GBC. Cell Counting Kit-8 and colony formation assays were performed to determine the effects of BRD9 on cell growth. The functional role of BRD9 in GBC was explored using qRT-PCR, western blotting, siRNA, and CHIP-qPCR. mRNA sequencing was performed to explore the underlying mechanisms of BRD9, and a nude mouse model of GBC was established to explore the anti-tumor effects of the BRD9 inhibitor I-BRD9 in vivo. BRD9 expression was elevated in GBC tissues compared with adjacent non-tumor tissues, and high BRD9 expression was associated with poor prognosis in patients with GBC. BRD9 knockdown by siRNA significantly decreased cell growth. Targeting BRD9 with I-BRD9 inhibited the proliferation of GBC cells without significant toxic effects. Additionally, I-BRD9 treatment suppressed CST1 expression in GBC cell lines, thereby inhibiting the PI3K-AKT pathway. The transcription factor FOXP1 was found to interact with BRD9 to regulate CST1 expression. Collectively, these results suggest that BRD9 may be a promising biomarker and therapeutic target for GBC.

Nicorandil Exerts Anticonvulsant Effects in Pentylenetetrazol-Induced Seizures and Maximal-Electroshock-Induced Seizures by Downregulating Excitability in Hippocampal Pyramidal Neurons.

N-(2-hydroxyethyl) nicotinamide nitrate (nicorandil), a nitrate that activates adenosine triphosphate (ATP)-sensitive potassium (KATP) channels, is generally used in the treatment of angina and offers long-term cardioprotective effects. It has been reported that several KATP channel openers can effectively alleviate the symptoms of seizure. The purpose of this study was to investigate the improvement in seizures induced by nicorandil. In this study, seizure tests were used to evaluate the effect of different doses of nicorandil by analysing seizure incidence, including minimal clonic seizure and generalised tonic-clonic seizure. We used a maximal electroshock seizure (MES) model, a metrazol maximal seizure (MMS) model and a chronic pentylenetetrazol (PTZ)-induced seizure model to evaluate the effect of nicorandil in improving seizures. Each mouse in the MES model was given an electric shock, while those in the nicorandil group received 0.5, 1, 2, 3 and 6 mg/kg of nicorandil by intraperitoneal injection, respectively. In the MMS model, the mice in the PTZ group and the nicorandil group were injected subcutaneously with PTZ (90 mg/kg), and the mice in the nicorandil group were injected intraperitoneally with 1, 3 and 5 mg/kg nicorandil, respectively. In the chronic PTZ-induced seizure model, the mice in the PTZ group and the nicorandil group were injected intraperitoneally with PTZ (40 mg/kg), and the mice in the nicorandil group were each given 1 and 3 mg/kg of PTZ at a volume of 200 nL. Brain slices containing the hippocampus were prepared, and cell-attached recording was used to record the spontaneous firing of pyramidal neurons in the hippocampal CA1 region. Nicorandil (i.p.) significantly increased both the maximum electroconvulsive protection rate in the MES model and the seizure latency in the MMS model. Nicorandil infused directly onto the hippocampal CA1 region via an implanted cannula relieved symptoms in chronic PTZ-induced seizures. The excitability of pyramidal neurons in the hippocampal CA1 region of the mice was significantly increased after both the acute and chronic administration of PTZ. To a certain extent, nicorandil reversed the increase in both firing frequency and proportion of burst spikes caused by PTZ (P < 0.05). Our results suggest that nicorandil functions by downregulating the excitability of pyramidal neurons in the hippocampal CA1 region of mice and is a potential candidate for the treatment of seizures.

"Olfactory three-needle" acupuncture enhances synaptic function in Aß1-42-induced Alzheimer's disease via activating PI3K/AKT/GSK-3ß signaling pathway.

Synaptic dysfunction and neuronal loss are related to cognitive impairment of Alzheimer's disease. Recent evidence indicates that regulating the phosphatidylinositol 3-Kinase (PI3K)/AKT/GSK-3ß pathway is a therapeutic strategy for improving synaptic plasticity in Alzheimer's disease. Here, we investigated "olfactory three-needle" effects on synaptic function and the PI3K/AKT/GSK-3ß signaling pathway in ß-amyloid1-42 (Aß1-42)-induced Alzheimer's disease rats. A three-needle olfactory bulb insertion for 28 days alleviated Aß1-42-induced Alzheimer's disease rats' cognitive impairment as assessed by performance in the Morris water maze test. Furthermore, the three-needle electrode inhibited neuro-apoptosis and neuro-inflammation. It significantly upregulated the protein expression of postsynaptic density protein 95, synaptophysin, and GAP43, indicating a protective effect on hippocampal synaptic plasticity. Additionally, the activation level of PI3K/AKT signaling and the phosphorylation inactivation of GSK-3ß were significantly enhanced by the "olfactory three-needle". Our findings suggested that the three-needle acupuncture is a potential alternative to improve synaptic plasticity and neuronal survival of Alzheimer's disease brain in rodents.

Anti-Tumor Effects of Astaxanthin by Inhibition of the Expression of STAT3 in Prostate Cancer.

Astaxanthin is a natural product gaining increasing attention due to its safety and anti-cancer properties. In this study, we investigated the mechanisms of the anti-cancer effects of astaxanthin on prostate cancer (PCa) cell lines using aggressive PCa DU145 cells. Also an instantaneous silenced cell line (si-STAT3) derived from DU145 and a control cell line (si-NK) were used for the MTT and colony formation assays to determine the role of astaxanthin in proliferation and colony formation abilities. Flow cytometry assays were used to detect the apoptosis of tumor cells. Migration and invasion assays detected the weakening of the respective abilities. Western blot and RT-PCR tests detected the levels of STAT3 protein and mRNA. Astaxanthin resulted in suppression of the proliferation of DU145 cells and the level of STAT3. The treatment of DU145 cells with astaxanthin decreased the cloning ability, increased the apoptosis percentage and weakened the abilities of migration and invasion of the cells. Furthermore, astaxanthin reduced the expression of STAT3 at protein and mRNA levels. The effects were enhanced when astaxanthin and si-STAT3 were combined. The results of animal experiments were consistent with the results in cells. Thus, astaxanthin inhibits the proliferation of DU145 cells by reducing the expression of STAT3.

A cooperative construction strategy for multi-parameter spatial variant random fields and its application in groundwater pollution risk assessment.

The spatial variability of hydrogeological parameters is a significant source of uncertainty in groundwater numerical modeling and has a certain risk impact on the prediction of pollutant migration and transformation. Current research has focused on the effects of single-parameter spatial variant random fields or utilizing random sampling methods to randomly combine multiple-parameter spatial variant random fields while ignoring the correlation between parameters. This paper proposes an innovative concept of associated random variables to construct multi-parameter synergistic spatial variant random fields, ensuring both the spatial variability and inherent correlation of the parameters. A hypothetical case was constructed, and the Monte Carlo sampling experiment based on computer simulation was used to assess groundwater pollution risks with multiple associated parameters. The results show that hydraulic conductivity and porosity are the main sensitive parameters. The associated random variable allows for the representation of positive correlation, negative correlation, and no correlation between the hydraulic conductivity and porosity. The pollutant mass concentrations in each observation well conform to the generalized extreme value distribution, and the pollution risks of each water well as well as the concentration distribution intervals of pollutants with different probabilities can be obtained. The influence of associated parameters on the cumulative risk of contaminants in observation wells and pollution degree range is only related to their mathematical distribution and is independent of correlations between parameters. This study addresses the issues of spatial variability and inherent correlation of hydrogeological parameters, which are of great significance for groundwater pollution risk assessment and the promotion of sustainable water quality management of groundwater resources.

Intracranial aneurysm rupture risk in northern China: a retrospective case-control study.

Background: Rupture of intracranial aneurysms (IAs) can cause subarachnoid hemorrhage (SAH), which leads to severe neurological dysfunction and even death. Exploring the risk factors for IA rupture and taking preventive measures accordingly can reduce or prevent the occurrence of SAH. Currently, there is still no consensus on the detrimental factors for IA rupture. Thus, our study aimed to investigate the risk factors of IA rupture in a population of northern China. Methods: We systematically collected the demographic features, medical history, and imaging data of aneurysms from patients with ruptured and unruptured IAs (UIAs) who attended the Department of Neurosurgery at the Second Hospital of Hebei Medical University from 2014 to 2019. All cases had been diagnosed by digital subtraction angiography. We excluded patients with SAH resulting from injuries, as well as those with vascular dissection and incomplete data. Finally, 1,214 patients including 616 with ruptured IAs and 598 with UIAs were collected for further analysis. A case-control study was conducted, in which multivariable logistic regression was used to analyze the risk factors for IA rupture. Results: Our multivariable logistic regression showed that anterior cerebral artery [odds ratio (OR) =2.413; 95% confidence interval (CI): 1.235-4.718], anterior communicating artery (OR =3.952; 95% CI: 2.601-6.006), posterior communicating artery (OR =2.385; 95% CI: 1.790-3.177), and anterior circulation branches (OR =3.493; 95% CI: 1.422-8.581) were risk factors for IA rupture, whereas patients with a history of cerebral infarction (OR =0.395; 95% CI: 0.247-0.631) and those with IAs located in the internal carotid artery (OR =0.403; 95% CI: 0.292-0.557) were less likely to have IA rupture. Conclusions: IAs at specific locations are prone to rupture. These IAs should be paid particular attention and preventive measures should be taken to reduce or prevent their rupture.

NONO promotes gallbladder cancer cell proliferation by enhancing oncogenic RNA splicing of DLG1 through interaction with IGF2BP3/RBM14.

Gallbladder cancer (GBC) is a highly malignant and rapidly progressing tumor of the human biliary system, and there is an urgent need to develop new therapeutic targets and modalities. Non-POU domain-containing octamer-binding protein (NONO) is an RNA-binding protein involved in the regulation of transcription, mRNA splicing, and DNA repair. NONO expression is elevated in multiple tumors and can act as an oncogene to promote tumor progression. Here, we found that NONO was highly expressed in GBC and promoted tumor cells growth. The dysregulation of RNA splicing is a molecular feature of almost all tumor types. Accordingly, mRNA-seq and RIP-seq analysis showed that NONO promoted exon6 skipping in DLG1, forming two isomers (DLG1-FL and DLG1-S). Furthermore, lower Percent-Spliced-In (PSI) values of DLG1 were detected in tumor tissue relative to the paraneoplastic tissue, and were associated with poor patient prognosis. Moreover, DLG1-S and DLG1-FL act as tumor promoters and tumor suppressors, respectively, by regulating the YAP1/JUN pathway. N6-methyladenosine (m6A) is the most common and abundant RNA modification involved in alternative splicing processes. We identified an m6A reader, IGF2BP3, which synergizes with NONO to promote exon6 skipping in DLG1 in an m6A-dependent manner. Furthermore, IP/MS results showed that RBM14 was bound to NONO and interfered with NONO-mediated exon6 skipping of DLG1. In addition, IGF2BP3 disrupted the binding of RBM14 to NONO. Overall, our data elucidate the molecular mechanism by which NONO promotes DLG1 exon skipping, providing a basis for new therapeutic targets in GBC treatment.

Predictors of unprovoked seizures in intracerebral hemorrhages.

BACKGROUND: Seizures are a common complication of intracerebral hemorrhage (ICH). We aimed to identify predictors of unprovoked seizures (US) after ICH in a Chinese cohort. METHODS: We retrospectively included patients with ICH admitted in the Second Hospital of Hebei Medical University between November 2018 and December 2020. Incidence and risk factors of US were identified with univariate and then multiple Cox regression analysis. We used χ2 test to compare incidence of US between groups with or without prophylactic anti-seizure medications (ASM) in patients with craniotomy. RESULTS: A total of 488 patients were included in the cohort, 58 (11.9%) patients developed US within 3 years after ICH. Analysis on the 362 patients without prophylactic ASM showed that craniotomy (HR 8.35, 95% CI 3.80-18.31) and acute symptomatic seizures (ASS) (HR 13.76, 95% CI 3.56-53.17) are independent predictors of US. No significant effect of prophylactic ASM use was found on incidence of US in ICH patients with craniotomy (P = 0.369). CONCLUSIONS: Craniotomy and acute symptomatic seizures were independent predictors for unprovoked seizures after ICH, suggesting that more attention should be paid for such patients during follow-up. Whether prophylactic ASM treatment benefits ICH patients underwent craniotomy remains uncertain.

A construction strategy for conservative adaptive Kriging surrogate model with application in the optimal design of contaminated groundwater extraction-treatment.

When the simulation-optimization model to optimize the groundwater extraction-treatment schemes is used, the construction of a surrogate model for the numerical simulation model has become an effective means to overcome the large calculation load of repeatedly calling the numerical model. However, there are still some problems in using the surrogate model, such as large training sample size, low accuracy, and poor optimization results. In this paper, a conservative adaptive Kriging surrogate model (CAKSM) was proposed by coupling the Kriging surrogate model, optimal solution adaptive sampling method (OSAS), and conservative prediction idea. Firstly, an initial Kriging surrogate model (IKSM) was built for the numerical simulation model of groundwater flow and solute transport. Then, the IKSM was coupled with the optimization model to construct the adaptive Kriging surrogate model (AKSM) by using OSAS. A safety margin was added to the AKSM to build the CAKSM. Finally, the simulation-optimization models based on IKSM, AKSM, and CAKSM were solved by the genetic algorithm, respectively. The results showed that the IKSM could well substitute for the simulation model. The AKSM significantly improved the approximation degree between the surrogate model and the simulation model at the optimal solution by supplementing a small number of new samples. CAKSM could effectively constrain the pollutant mass concentrations within the controlled value, improving the reliability of the optimization scheme. The optimal extraction wells based on different surrogate models were all well 5, well 6, and well 9. They were concentrated in the middle and lower reaches of the contaminated plume's central axis. The sequence for the remediation effects by different surrogate models from high to low was as follows: CAKSM, AKSM, and IKSM. The risk rate of the optimal remediation scheme from the hydraulic conductivity random fields was as high as 12.12%, and the risks were mainly located upstream of the pollution plume's central axis.

Guillain-Barré Syndrome in Northern China: A Retrospective Analysis of 294 Patients from 2015 to 2020.

Objectives: Acute motor axonal neuropathy (AMAN) was first reported to be the main subtype of Guillain−Barré syndrome (GBS) in northern China in the 1990s. About 30 years has passed, and it is unknown whether the disease spectrum has changed over time in northern China. We aimed to study the epidemiological, clinical, and electrophysiological features of GBS in northern China in recent years. Methods: We retrospectively analyzed the medical records of GBS patients admitted to the Second Hospital of Hebei Medical University in northern China from 2015 to 2020. Results: A total of 294 patients with GBS were enrolled, with median age 53 years and 60.5% of participants being male, and a high incidence in summer and autumn. AMAN was still the predominant subtype in northern China (40.1%). The AMAN patients had shorter time to nadir, longer hospitalization time, and a more severe HFGS score at discharge than acute inflammatory demyelinating polyneuropathies (AIDP) (p < 0.05). With SPSS multivariable logistic regression analysis, we found the GBS disability score (at admission), dysphagia, and dysautonomia were independent risk factors for GBS patients requiring MV (p < 0.05). In comparison with other regions, the proportion of AMAN in northern China (40.1%) was higher than in eastern (35%) and southern (19%) China. Conclusions: AMAN is still the predominant subtype in northern China after 30 years, but there have been changes over time in the GBS spectrum since the 1990s. There are regional differences in GBS in China.

"Olfactory Three-Needle" Enhances Spatial Learning and Memory Ability in SAMP8 Mice.

As one of the most important therapies in complementary and alternative medicine, acupuncture has been used in the treatment of Alzheimer's disease (AD). Acupuncture of "olfactory three-needle" manipulation can improve the cognitive ability of AD patients. However, the mechanism of "olfactory three-needle" in AD remains largely unknown. Here, we identified that the "olfactory three-needle" therapy and eugenol olfactory stimulation both reduced the deposition of ß-amyloid (Aß) protein and increased the expression of synaptophysin (SYP), but only the "olfactory three-needle" enhanced the spatial learning and memory ability of SAMP8. Remarkably, the "olfactory three-needle" inhibited the phosphorylation of p38MAPK and the excessive activation of microglia (MG) in the hippocampus. Our study demonstrates that the "olfactory three-needle" enhances spatial learning and memory ability by inhibiting the phosphorylation of p38MAPK and the excessive activation of MG to reduce the neuroinflammatory response and neurotoxicity of Aß and promote synaptic regeneration, but it was not completely consistent with the stimulation of the olfactory system.

Age-related alterations in the metabolic profile in the hippocampus of the senescence-accelerated mouse prone 8: a spontaneous Alzheimer's disease mouse model.

Alzheimer's disease (AD), the most common age-dependent neurodegenerative disorder, produces a progressive decline in cognitive function. The metabolic mechanism of AD has emerged in recent years. In this study, we used multivariate analyses of gas chromatography-mass spectrometry measurements to determine that learning and retention-related metabolic profiles are altered during aging in the hippocampus of the senescence-accelerated mouse prone 8 (SAMP8). Alterations in 17 metabolites were detected in mature and aged mice compared to young mice (13 decreased and 4 increased metabolites), including metabolites related to dysfunctional lipid metabolism (significantly increased cholesterol, oleic acid, and phosphoglyceride levels), decreased amino acid (alanine, serine, glycine, aspartic acid, glutamate, and gamma-aminobutyric acid), and energy-related metabolite levels (malic acid, butanedioic acid, fumaric acid, and citric acid), and other altered metabolites (increased N-acetyl-aspartic acid and decreased pyroglutamic acid, urea, and lactic acid) in the hippocampus. All of these alterations indicated that the metabolic mechanisms of age-related cognitive impairment in SAMP8 mice were related to multiple pathways and networks. Lipid metabolism, especially cholesterol metabolism, appears to play a distinct role in the hippocampus in AD.

Repetitive transcranial magnetic stimulation applications normalized prefrontal dysfunctions and cognitive-related metabolic profiling in aged mice.

Chronic high-frequency repetitive transcranial magnetic stimulation (rTMS) is a noninvasive brain stimulation technique that has recently received increasing interests as a therapeutic procedure for neurodegenerative diseases. To identify the metabolism mechanism underlying the improving effects of rTMS, we observed that high frequency (25Hz) rTMS for 14 days could reverse the decline of the performance of the passive avoidance task in aged mice. We further investigated the metabolite profiles in the prefrontal cortex (PFC) in those mice and found that rTMS could also reverse the metabolic abnormalities of gamma-aminobutyric acid, N-acetyl aspartic, and cholesterol levels to the degree similar to the young mice. These data suggested that the rTMS could ameliorate the age-related cognitive impairment and improving the metabolic profiles in PFC, and potentially can be used to improve cognitive decline in the elderly.

Age-related autophagy alterations in the brain of senescence accelerated mouse prone 8 (SAMP8) mice.

Autophagy is responsible for the degradation of long-lived proteins and damaged organelles intracellular, even extracellular,and autophagy is proved to have relationship with Alzheimer's disease (AD) and aging. The senescence accelerated mouse prone 8 (SAMP8) was a non-genetically modified mice widely used as a rodent model of aging and senile dementia. However, little was known about the age-related changes of autophagy in the brain of SAMP8 mice. To better understand the precise relationship between aging, autophagy and neurodegeneration, we explored the time course of cognitive ability, ubiquitin-positive inclusions, ultrastructure of neurons and detected the expression of LC3 and Beclin 1 protein in different brain regions of 2, 7 and 12-month-old SAMP8 and SAMR1 mice. We found that 7 and 12-month-old SAMP8 mice presented cognitive decline and ubiquitinated proteins enhanced. In the hippocampal neurons of 12-month-old SAMP8 mice, lots of dense clumps and autophagic vacuoles were found in the cytoplasm and axons. The LC3-II expression showed an increase in hippocampus and cortex of 7 and 12-month-old SAMP8 mice. The expression of Beclin 1 displayed a significant increase in 7 months old and a decline in 12 months old mice. Based on these data, we suggest that the autophagic activity maybe increase reactively at the beginning of AD and then showed a decline with aging, and the pathological changes of 12-month-old SAMP8 mice are more similar to the late-onset AD in the perspective of autophagy.

Biodegradation of anthracene by Aspergillus fumigatus.

An anthracene-degrading strain, identified as Aspergillus fumigatus, showed a favorable ability in degradation of anthracene. The degradation efficiency could be maintained at about 60% after 5d with initial pH of the medium kept between 5 and 7.5, and the optimal temperature of 30 °C. The activity of this strain was not affected significantly by high salinity. Exploration on co-metabolism showed that the highest degradation efficiency was reached at equal concentration of lactose and anthracene. Excessive carbon source would actually hamper the degradation efficiency. Meanwhile, the strain could utilize some aromatic hydrocarbons such as benzene, toluene, phenol etc. as sole source of carbon and energy, indicating its degradation diversity. Experiments on enzymatic degradation indicated that extracellular enzymes secreted by A. fumigatus could metabolize anthracene effectively, in which the lignin peroxidase may be the most important constituent. Analysis of ion chromatography showed that the release of anions of A. fumigatus was not affected by addition of anthracene. GC-MS analysis revealed that the molecular structure of anthracene changed with the action of the microbe, generating a series of intermediate compounds such as phthalic anhydride, anthrone and anthraquinone by ring-cleavage reactions.

Genetic polymorphism of 11 Y-chromosomal STR loci in Yunnan Han Chinese.

Allele frequencies and haplotypes of 11 Y-chromosome STR loci, DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS385 ab, DYS438, DYS439 and DYS437 were determined in 320 unrelated Yunnan Han Chinese males. A total of 293 haplotypes were identified, of which 268 were unique, 23 were shared in two individuals, and 2 were shared in three individuals. The allele diversity values for each locus ranged from 0.4087 (DYS438) to 0.9701 (DYS385). The allele observed haplotypes diversity value was 0.9994. The combined Y-chromosome STR polymorphisms provide a powerful discrimination tool for routine forensic applications.

[Isolation of an anthracene-degrading strain Aspergillus fumigatus A10 and its degradation characteristics].

An anthracene-degrading strain (A10) was isolated from contaminated environment and identified as Aspergillus fumigatus. The experimental results showed that the biodegradation rate of anthracene increased with the increasing time. Between 12-84 h interval, the biodegradation performed rapidly, while after this, the increase of biodegradation rate tended to become slow, and ultimately the biodegradation rate could achieve approximately 83%. The degradatinn rate of anthracene reached 79.37% within 5 days when the initial concentration of anthracene in mineral salts medium (MSM) was 10 mg/L, the inoculum dosage was 50 g/L (wet weight) and the cell age was 36 h. The concentration of anthracene had notable influence on degradation function of strain A10 and the highest degradation rate (92.17%) was achieved when anthracene concentration was 5 mg/L. The degradation rate could maintain about 60% with initial pH of MSM in the range of 5.0-7.5, and also, the anthracene could be better broken down when the temperature was 30 degrees C and dissolved oxygen was 4.30 mg/L. Certain amount of nutrition salts promoted the biodegradation of anthracene to some extent. Addition of lactose as co-metabolic substrate most favorably accelerated degradation of anthracene by about 37.15%. The mechanism research revealed that the biodegradation by strain A10 was a dynamic process in which extracellular sorption and intracellular degradation were included. FT-IR analysis exhibited that the structure of anthracene changed with the action of microbe, generating a series of metabolites, such as aromatic acid, aromatic ketone, aromatic aldehyde with one or two benzene rings, as well as saturated hydrocarbons.

[Characteristics and pathway of naphthalene degradation by Pseudomonas sp. N7].

The biodegradation characteristics of a typical polycyclic aromatic hydrocarbon, naphthalene by the strain (Pseudomonas sp. N7) were investigated by using HPLC and UV analytical techniques. The results showed that the addition of nutritious salt and microelements accelerated the degradation of naphthalene by 23.65%. Degradation efficiency increased with increasing dissolved oxygen and reached 95.66%, then remained stabilized when dissolved oxygen was over 4.3 mg/L, yet decreased with increasing naphthalene concentration. Neutral and weak alkaline condition favored the biodegradation with degradation capacity all over 82.88%. Pseudomonas sp. N7 had a maximum degradation capability of 95.66% when dealing with 100 mg/L naphthalene at 30 degrees C and pH 7.5 with 165 r/min rotary shaking for 72 h. By measuring the absorbance, pH and degradation of substrates during treatment of different substrate with strain N7, it was demonstrated that Pseudomonas sp. N7 could also degrade other aromatic hydrocarbons, such as toluene, dimethylbenzene, phenol, 2,4-nitrophenols, benzyl acid, 1-naphthol and salicylic acid, utilizing each of them as sole carbon and energy source for growth and breeding, thus showing its good biodegradation diversity. The pathway of naphthalene degradation was explored through analyzing metabolic intermediates at different degradation stages by using UV-Vis and GC-MS. The result revealed that there were two possible degradation pathways for naphthalene: one was phthalic acid pathway, and the other was that naphthalene was first oxidized to 1,2-dihydroxynaphthalene, and then the cleavage of rings caused the formation of salicylic acid, catechol, and 2-hydroxymuconic semial-dehyde. Finally these metabolites entered the tricarboxylic acid cycle (TCA).